It comes in a small teal box with a label that reads "New Boomerang Pet Ball. Really Works!," with the word "new" imprinted in light green text within a dark green explosion banner, the words "boomerang pet ball" in white text within a dark red wide diagonal line across the box, and the words "really works" in yellow text within a small brown line.
The ball itself is a boomerang, hence the name. It can be thrown and returns to whoever threw it.
Role in episode
When SpongeBob attempts to get Gary to take a bath, he throws the ball towards the bathtub. However, the ball bounces back to him. Later, SpongeBob throws the box, but it bounces back at his head when he begins to walk away.